Common Ringtail Possum (Pseudocheirus peregrinus) of Australia's Eastern Coasts and Islands

The designation ringtail possum currently acknowledges 17 living species within the marsupial family Pseudocheiridae. The family name addresses as the most important ringtail commonality the structural feature of grasping paws reminiscent of humans in the presence of opposable digits. It comes from the combination of the ancient Greek words ψευδής (pseudēs, “beguiled, deceived, false, lying, untrue”), χειρό- (cheiró-, “hand”), and εἶδος (eidos, “appearance, look, sight”). But all ringtail possums additionally draw attention to the aesthetic and functional look of their beautifully practical tails. A ringtail possum’s tail ends in an attractive tip that frequently is coiled or ready to coil as a grasping anchor or balance and that sometimes may be slightly -- or starkly -- different in color.

Common ringtail possums are perhaps the best known and the most accessible of all ring-tailed possums. They carry the binomial (“two names”) taxonomic designation Pseudocheirus peregrinus. The species name goes back to the Latin word peregrīnus. It has the meaning of “alien, exotic, foreign” as a masculine adjective and of “foreigner, traveler” as a masculine noun. It therefore hypothesizes a migrant, pilgrim or wanderer who may be here one minute and go missing the next. It currently includes four subspecies:

• Pseudocheirus peregrinus peregrinus;
• P.p. convolutor (from the Latin masculine past participle convolūtus for “rolled up”);
• P.p. pulcher (from the Latin masculine adjective pulcher for “beautiful, fair”);
• P.p. occidentalis. (from the Latin feminine/masculine adjective occidentālis for “westerly, western”).

The four subspecies of the common ringtail possum articulate differences in geographical distribution and variations in pelt color. By merging distinct and overlapping environmental niches, scientists attribute to common ringtail possums a spatial presence that is most notable in:

• Bass Strait islands;
• Coastal eastern Australia at New South Wales, Queensland, and Victoria;
• Fraser Island;
• New Guinea;
• Tasmania.

Southwestern-most West Australia belongs on the list of places to find common ringtail possums as long as scientists do not reduce the number of subspecies to three. Some experts expect the fourth subspecies, Pseudocheirus peregrinus occidentalis, to be upgraded to species status as Pseudocheirus occidentalis. Others find geographical isolation and structural variations nevertheless consistent with the western ringtail’s subspecies status.

Colors act as camouflage by catching the play of light and shadow in the coastal and near-coastal habitats of common ringtail possums.  Grey-brown covers the upper body. Grey-, orange- and red-brown dominates the limbs. White embellishes:

• Big brown eyes;
• Pink nose and rounded ears;
• Sensory whiskers.

It emerges from a mouth of teeth whose dental formula configures:

• 6 incisors, 2 canines, 6 premolars, and 8 molars equally divided between the left and right upper jaws;
• 4 incisors, 6 premolars, and 8 molars evenly spread over the left and right lower jaws.

It ends the bottom third of a prehensile tail that is:

• Coiled when unused;
• Dark at the base;
• Hairless at the tip and underneath;
• Furry above.

The yearly breeding months are March through November. From sexual maturity at 12 months onward, ringtails become parents to twins or triplets once or twice yearly, with litters delivered during the months of:

• May to July;
• October.

As the only possum species that includes paternal involvement in caring for and raising the young, both parents-to-be build dreys (spherical nests) of shredded bark, grasses and leaves. Gestation demands 4 months. Hairless newborns enter the frontal maternal pouch without parental assistance. They have their ears and eyes opened 3 – 3-1/2 months after birth. At 4 months, they move from pouch-living on 4 mammary sources of maternal milk to nomadic life in the family dreys and on their parents’ backs.

Immature ringtail possums begin eating solid food upon emerging from maternal pouches. The timing coordinates with peak freshness of flowers, fruits, leaves, and nectar of:

• Bottle brush (Callistemon, Grevillea);
• Eucalyptus and gum (Angophora, Corymbia, Eucalyptus);
• Oleander and wattle (Acacia);
• She-oak (Allocasuarina);
• Tea tree (Leptospermum).

The rufous (red-brown) youths dominate:

• Communicating by high-pitched, soft twitters;
• Foraging and foraying, dusk to midnight and pre-dawn;
• Producing hard nocturnal pellets for territory-marking and soft diurnal pellets for rabbit-like coprophagia (digestion and re-elimination after nutrient access, especially of soluble nitrogen).

They live independently at 8 – 12 months. They mature to:

• Head-and-body and tail lengths, generally of 11.75 – 13.75 inches (29.84 – 34.92 centimeters) respectively;
• Weights, typically of 1.25 – 3 pounds (566.99 – 1,360.78 grams). 

Paired common ringtail possums adhere to nomadic living within scent-marked home ranges of 7.5 acres (3.03 hectares). They commence with a minimum of five dreys, whose number increases with every litter. They construct their series of football-sized nests along canopied branches, on higher forks, and within upper hollows in dense shrubs and trees 6.5+ feet (2+ meters) above ground-level. They enter by a 3.25 – 4-inch (8.26 – 10.16-centimeter) side entrance. Each 9.75 – 11.75 (24.76 – 29.84-centimeter) nest fits several, who sleep with bodies and tails curled tightly into small balls. An arboreal, gregarious, nocturnal, nomadic life cycle around and within homey nests which they build themselves therefore is what common ringtail possums historically expect for themselves and their descendants.

But the security of the past does not continue unabated into the present -- and therefore possibly the future -- of the common ringtail possum. Common ringtail possums consequently expect current lifespans of 3 years in the wild and 10 – 12 years in captivity. They in fact face so many environmental challenges that at least one newborn per year generally cannot expect to survive the first year of existence. They find that their traditional habitats are prime locations for the widening wildland-urban interface in Planet Earth’s super-island continent and country “down under.”  Common ringtail possums indeed inhabit coastal, insular and near-coastal niches within Australia’s diverse expressions of dense temperate and tropical brush in:

• Forests;
• Heathlands;
• Shrublands;
• Woodlands. 

Common names accentuate the common ringtail possum’s predictable colors and distribution:

• Eastern ringtail;
• Grey ringtail;
• Queensland ringtail;
• Rufous ringtail;
• Tasmanian ringtail;
• Western ringtail.

Conservation statisticians generally apply an unthreatened status to the three eastern subspecies of this buck-toothed diprotodont (“two forward-projecting teeth”) despite:

• Habitat destruction and fragmentation;
• Predation by dingoes, foxes, owls, and pythons;
• Road fatalities;
• Wildfire casualties.

They simultaneously attribute vulnerability status to the western subspecies affectionately nicknamed ngwayir. But conservation-minded professionals and supporters fortunately endeavor to include within Australia’s future all four “false-handed” subspecies, each of whose forepaws' two opposable digits so impressed Middleburg-born Dutch naturalist and Elenchus Animalium publisher Pieter Boddaert (May 26, 1733 – May 6, 1795) with their dexterity way back in 1785.  

My special thanks to talented artists and photographers/concerned organizations who make their fine images available on the internet.

Ellis Troughton, Furred Animals of Australia (1947), Plate VIII, Figure 1, opp. p. 112: Public Domain, via Wikimedia Commons @ https://commons.wikimedia.org/wiki/File:Pseudocheirus_peregrinus-Cayley.jpg

Currie, central western coast of King Island, Great Australian Bight, Tasmania, southeastern Australia: Karl Barnfather at English Wikipedia, Public Domain, via Wikimedia Commons @ https://commons.wikimedia.org/wiki/File:Currie_Harbour-King_Island-Australia.jpg

"Distribution data from IUCN Red List.": Chermundy / IUCN Red List of Threatened Species, CC BY SA 3.0, via Wikimedia Commons @ https://en.wikipedia.org/wiki/File:Common_Ringtail_Possum_area.png

"Distribution data from IUCN Red List.": Chermundy / IUCN Red List of Threatened Species, CC BY SA 3.0, via Wikimedia Commons @ https://en.wikipedia.org/wiki/File:Western_Ringtail_Possum_area.png

Plate XIX, Figure 2: Public Domain, via Biodiversity Heritage Library @ http://biodiversitylibrary.org/page/37986833

Plate XVIII, Figure 5: Public Domain, via Biodiversity Heritage Library @ https://www.biodiversitylibrary.org/page/37986831

Eucalyptus maculata (Spotted Gum) flower and foliage; Drysdale, Bellarine Peninsula, Victoria state, southeast Australia: Rexness from Melbourne, Australia, CC BY SA 2.0, via Wikimedia Commons @ https://commons.wikimedia.org/wiki/File:Eucalyptus_maculata_(1).jpg?uselang=de

"peeking possum: orphaned ringtails in their pouch": Lee (ljhar6), CC BY 2.0, via Flickr @ https://www.flickr.com/photos/32384322@N04/3026203403/

Brisbane, southeastern Queensland state, east Australian coast: Glen Fergus, CC BY SA 2.5, via Wikimedia Commons @ https://en.wikipedia.org/wiki/File:Common_Ringtail_Possum.jpg

Ninox strenua munching on ring tailed possum (Pseudocheirus peregrinus): David Lochlin, CC BY 2.0, via Flickr @ https://www.flickr.com/photos/74747209@N05/7555350268/

John Gould, Mammals of Australia, Vol. I, Plate 19: Public Domain, via Wikimedia Commons @ https://commons.wikimedia.org/wiki/File:Pseudocheirus_peregrinus_2_Gould.jpg

dead possum; Melbourne, Victoria, southeastern Australia: Jes (mugley), CC BY-SA 2.0, via Flickr @ https://www.flickr.com/photos/91256982@N00/219775166

ringtail possum: Benjamint444, CC BY SA 3.0, via Wikimedia Commons @ https://en.wikipedia.org/wiki/File:Possum_Ring-tailed444.jpg

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